Method for controlling a fan of an electronic photo device

Abstract

Disclosed is a method for controlling the operation of a fan in an electronic photo device including a developing device, a fan for keeping the temperature in the electronic photo device uniformly, and an output sensor for sensing output of a printed paper. According to the method, when a printable medium to be printed with print data is located between a transferring roller and an OPC drum of the developing device, the sort of the printable medium is determined. If it is determined that the printable medium is a first printable medium, the fan is stopped and a fixing process is performed. Otherwise, if it is determined that the printable medium is a second printable medium, the fixing step is performed under the condition that the fan is not stopped.

What is claimed is:  
     
       1. A method for controlling operation of a fan in an electronic photo device, comprising the steps of: 
       when a printable medium to be printed with print data is located between a transferring roller and an organic photo conductive (OPC) drum of a developing device of the electronic photo device, determining what sort of printable medium is the printable medium;  
       when said printable medium is a first sort of printable medium, stopping the operation of a fan for keeping the temperature uniform in the electronic photo device and performing a fixing process; and  
       when said printable medium is a second sort of printable medium, performing said fixing process under the condition that said fan is not stopped.  
     
     
       2. The method of claim  1 , wherein said second sort of printable medium includes overhead projector film. 
     
     
       3. The method of claim  1 , wherein said first sort of printable medium includes general paper. 
     
     
       4. The method of claim  1 , wherein said sort of said printable medium is determined by measuring a resistance value of said printable medium. 
     
     
       5. The method of claim  1 , further comprising the steps of: determining whether an upper end ofthe fixed printable medium is passed by an output sensor; 
       when said upper end of the fixed printable medium is passed by said output sensor,  
       and when the fixed printable medium is said first sort of printable medium, stopping said fan and operating said fan when a bottom end of said first printable medium is passed by said output sensor, and  
       when the fixed printable medium is said second sort of printable medium, operating said fan after said second printable medium is passed by a predetermined point from said output sensor; and  
       terminating a printing process.  
     
     
       6. The method of claim  5 , wherein said predetermined point is 25 mm from said output sensor. 
     
     
       7. The method of claim  5  further comprising the step of, after said printing process is terminated, operating said fan at a predetermined rotating speed for a predetermined time. 
     
     
       8. The method of claim  7 , wherein said predetermined time is 30 seconds. 
     
     
       9. The method of claim  7 , wherein said predetermined rotating speed is 60 to 70% of a normal rotating speed of said fan. 
     
     
       10. A method for operating an electrophotographic device, comprising the steps of: 
       when a print order is received, then operating a fan for cooling a fixing unit of the electrophotographic device, and picking up a paper for printing;  
       transferring the picked up paper to the space between a transferring roller and an organic photoconductive drum of the electrophotographic device;  
       determining whether the transferred paper is an overhead projector film;  
       when the transferred paper is not an overhead projector film, then stopping said fan and fixing the transferred paper in the fixing unit; and  
       when the transferred paper is an overhead projector film, then continuing to operate the fan and fixing the transferred paper in the fixing unit.  
     
     
       11. The method of claim  10 , further comprising: 
       when the leading edge of a fixed paper which is not an overhead projector film passes a predetermined point at a predetermined distance from an output sensor, then operating said fan; and  
       when the leading edge of a fixed paper which is an overhead projector film passes said output sensor, then stopping the fan, and when the trailing edge of the fixed paper passes said output sensor, then restarting the fan.  
     
     
       12. The method of claim  11 , the predetermined distance being approximately 25 mm. 
     
     
       13. The method of claim  11 , further comprising the step of: 
       after the fixed paper is output from the electrophotographic device, then operating the fan for a predetermined period and then stopping the fan.  
     
     
       14. The method of claim  13 , said step of operating the fan for a predetermined time comprising operating the fan for approximately 30 seconds. 
     
     
       15. The method of claim  13 , said step of operating the fan for a predetermined time comprising operating the fan at a speed in the range of approximately 60 to 70% of a normal rotation speed. 
     
     
       16. The method of claim  10 , said step of determining whether the paper is an overhead projector film comprising measuring the resistance value of the paper.